Concealed object detection

ABSTRACT

Disclosed are systems, methods, devices, and apparatus to interrogate a clothed individual with electromagnetic radiation to determine if a concealed weapon is being carried. This determination includes establishing data corresponding to an image of the individual and processing data sets corresponding to a number of spatial frequency representations of different image portions to evaluate if the concealed weapon is present.

BACKGROUND

The present invention relates to detection of concealed objects, andmore particularly, but not exclusively relates to detecting weapons orcontraband carried by a person beneath clothing.

The detection of weapons, contraband, and other concealed objects is ofsignificant interest at security checkpoints and the like. One approachutilizes a magnetometer to detect certain metallic objects.Unfortunately, this approach does not detect most organic polymer andcomposite materials that may be used to fabricate firearms, explosives,and other objects which are frequently the subject of securityinspections.

In another approach, millimeter wave electromagnetic radiation isapplied to provide images that can reveal objects concealed by clothing.This approach typically depends on the ability of a human inspector tovisually detect one or more suspect objects from the resulting image.Accordingly, there are intrinsic speed limitations in these approaches,and such approaches are subject to variation with the ability ofdifferent inspectors. Moreover, because these systems can providedetailed images of body parts that are ordinarily intended to be hiddenby clothing, utilization of a human inspector can be embarrassing to theperson being inspected, and may pose a concern that privacy rights arebeing violated. Thus, there is an on going demand for furthercontributions in this area of technology.

SUMMARY OF INVENTION

One embodiment of the present invention is a unique technique to detectobjects. Other embodiments include unique systems, devices, methods, andapparatus to determine if a person is carrying a concealed man-madeobject.

A further embodiment of the present invention includes a technique toscan a clothed person with electromagnetic radiation and determine if aman-made object is being carried by the person beneath their clothing.This determination can be made by analysis of image data from the scanwith one or more processors to identify one or more image regionssuspected of revealing a concealed man-made object. These regions canthen be displayed for verification by a human inspector. As a result,only those portions of an image suspected of revealing concealed objectsare subject to human inspection. Optionally, the processor analysis canbe arranged to discriminate between different types of man-made objects.In one form, analysis focuses on the detection of weapons or contraband.As used herein, a weapon includes, but is not limited to, a knife,firearm, gun, explosive, bomb, incendiary device, gas or particledispensing device, or any portion thereof. Alternatively oradditionally, a different type of man-made object may be the subject ofdetection in other forms of such embodiments.

In another embodiment, a person is irradiated by electromagneticradiation within a frequency range of about 200 Megahertz (MHz) to about1 Tetrahertz (THz). Data representative of an image of the person isestablished from the irradiation and several data sets are determinedfrom this data. The data sets each correspond to a spatial frequencyrepresentation of a different portion of the image. The data sets areadaptively processed to identify a man-made object being carried by theperson. In one form, the data set determination includes performing aFourier transform operation with different portions of the data toprovide respective spatial frequency data representations, and applyingan image feature extraction filter to each of the spatial frequency datarepresentations to correspondingly provide the data sets for adaptiveprocessing.

Still another embodiment of the present invention includes: establishingdata corresponding to an image of a concealed surface by irradiatingwith electromagnetic radiation including one or more frequencies in arange of about 200 MHz to about 1 THz, generating a data setcorresponding to a spatial frequency representation of at least aportion of the image from the data, and identifying a concealed man-madeobject by analyzing the data with a neural network. In one form, thedata can be established by performing a scan of a person in a portal ata security check point with the electromagnetic radiation, and theconcealed man-made object is at least one of a weapon and contraband.

Yet another embodiment includes: irradiating a person at least partiallycovered with clothing, detecting electromagnetic radiation reflectedfrom a surface beneath the clothing in response, establishing datacorresponding to a spatial frequency representation of the surface fromthe radiation, and analyzing the data with a neural network to identifya man-made object being carried by the person beneath the clothing.

A further embodiment of the present invention includes irradiating aperson at least partially covered by clothing with electromagneticradiation including one or more frequencies in a range of 200 MHz toabout 1 THz, and in response, establishing data representative of animage of the person that may include details of one or more body partsthat are normally hidden by the clothing. Several data sets aredetermined each corresponding to a respective one of a number ofdifferent image portions that are numerically processed relative to oneor more criteria to evaluate if one or more of the different imageportions reveals a man-made object beneath the clothing. If the one ormore criteria are satisfied, an image of the man-made object isdisplayed relative to a location on the person. Accordingly, if theseone or more criteria are not satisfied, then an image of the person neednot be displayed. Indeed, even when an image is displayed, it can belimited to a region proximate to its location on the person's bodyand/or can be shown relative to a gender-neutral representation of theperson, such as a silhouette, wire-frame outline, mannequin, or thelike.

Another embodiment of the present invention includes a system with asensing array operable to interrogate a person with electromagneticradiation and one or more processors operable to establish datarepresentative of an image of the person from one or more input signalsprovided by the array. The one or more processors are operable togenerate a number of data sets each corresponding to a spatial frequencyrepresentation of a different portion of the image from the data andanalyze the data sets with a neural network to detect if the person iscarrying a man-made object.

In still another embodiment, an apparatus includes a device carryinglogic executable by one or more processors to process data correspondingto an image of a person obtained from electromagnetic radiationincluding one or more frequencies in a range of about 200 MHz to about 1THz. The logic is further operable to generate a number of data setseach corresponding to a spatial frequency representation of a respectiveone of a number of different portions of the image and adaptivelyprocess each of these data sets relative to one or more criteria todetermine if one or more of the different portions of the image show anobject. The logic provides signals to display at least a portion of theobject relative to a location on the person if the one or more criteriaare satisfied. In one form, the logic is further operable to perform aFourier transform operation with different portions of the data tocorrespondingly provide a number of sets of spatial frequency data, andapply an image feature filter to each of the sets of spatial frequencydata to correspondingly provide the data sets for adaptive processing.In another form, the logic alternatively or additionally defines aneural network to perform the adaptive processing of the data sets.

Accordingly, one object of the present invention is to provide a uniquetechnique to detect objects, weapons, and/or contraband.

Another object is to provide a unique system, method, or apparatus todetermine if a person is carrying a concealed device, object, ormaterial of interest.

Other objects, embodiments, forms, features, advantages, aspects andbenefits of the present invention shall become apparent from thedetailed description and drawings included herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial, diagrammatic view of a security inspection system.

FIG. 2 is a partial, top view of the FIG. 1 system along the view line2—2 shown in FIG. 1.

FIGS. 3-5 are flow charts illustrating one procedure for operating thesystem of FIG. 1.

FIG. 6 is a schematic, top view of the system of FIG. 1 illustrating anumber of overlapping arc segments.

FIG. 7 is a diagram illustrating segmentation of an image intooverlapping rectangular portions for use in the procedure of FIGS. 3-5.

FIG. 8 is a diagram comparing three different types of featureextraction filters for use with the procedure of FIGS. 3-5.

FIG. 9 is a partial, diagrammatic view of another system.

FIG. 10 is a partial, cut-away view of the portal shown in FIG. 9.

FIG. 11 is a partial, diagrammatic view of still another system.

FIG. 12 is a partial, diagrammatic view of yet another system.

FIG. 13 is a partial, top view of the system of FIG. 12.

DETAILED DESCRIPTION

While the present invention may be embodied in many different forms, forthe purpose of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended. Any alterations and further modificationsin the described embodiments, and any further applications of theprinciples of the invention as described herein are contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

FIG. 1 illustrates security inspection system 20 of one embodiment ofthe present invention. In operation, system 20 interrogates an animateor inanimate object by illuminating it with electromagnetic radiation inthe 200 Megahertz (MHz) to 1 Terahertz (THz) frequency range anddetecting the reflected radiation. Generally, the correspondingwavelengths range from several centimeters to a few micrometers. Certainnatural and synthetic fibers are often transparent or semi-transparentto such frequencies/wavelengths, permitting the detection and/or imagingof surfaces positioned beneath such materials. When the subject ofinterrogation is a clothed individual, image information about portionsof a person's body covered by clothing or garments can typically beobtained with system 20, as well as those portions that are not coveredby clothing or garments. Further, image information relative to objectscarried by a person beneath clothing can be provided with system 20 formetal and non-metal object compositions commonly used for weapons andcontraband.

As illustrated in FIG. 1, body B is in the form of a person 22 presentedfor interrogation by system 20. Person 22 is portrayed in a typicalmanner, being at least partially covered by garments or clothingdesignated more specifically by reference numerals 24 a and 24 b.Clothing items 24 a and 24 b conceal object 25 shown in the form of aweapon in phantom. Person 22 is positioned in scanning/illuminationportal 30 of system 20. Portal 30 is configured for placement at asecurity checkpoint of the type where it is desired to detect weaponsand/or contraband. Portal 30 includes platform 32 connected to motor 34.Platform 32 is arranged to support person 22 or such other objectdesired to be examined with system 20. Motor 34 is arranged toselectively rotate about rotational axis R while person 22 is positionedthereon. For the orientation shown, axis R is approximately vertical,and person 22 is in a generally central position relative to axis R andplatform 32. In one form, platform 32 can be comprised of a material,such as an organic thermoplastic or thermoset polymer, that permits theinterrogation in or beneath the soles of shoes where weapons cansometimes be hidden.

Portal 30 further includes multiple element-sensing array 36. Referringadditionally to the partial top view of FIG. 2, the relationship ofplatform 32 to array 36 is further illustrated. Axis R is generallyperpendicular to the view plane of FIG. 2 and is represented bycrosshairs. As motor 34 causes platform 32 to rotate about axis R, array36 circumscribes a generally circular pathway P about axis R. Circularpathway P corresponds to an imaginary cylinder C with radius D. Radius Dis the distance from axis R to array 36. In one preferred form, radius Dis about 0.5 to about 2 meters. In a more preferred form, radius D isabout 0.5 meters to 1.5 meters—corresponding to about a 1 meter to 3meter diameter. Arrow A shown in FIGS. 1 and 2 represents the selectiverotation of platform 32 about axis R.

Sensing array 36 includes a number of linearly arranged elements 38 onlya few of which are schematically illustrated and specifically designedby reference numerals to preserve clarity. Elements 38 each operate totransmit or receive electromagnetic radiation within a selectedbandwidth. Sensing array 36 is coupled to processing subsystem 40.Subsystem 40 includes transceiver 42 with switching tree 43 coupled toelements 38 of array 36. In one form, the position of array 36 relativeto platform 32 is determined with one or more positional encoders (notshown) that are coupled to subsystem 40. In other forms, one or moredifferent position tracking devices and/or techniques can be used.

Under the control of transceiver 42, individual elements 38 can beselectively activated with switching tree 43. Each element 38 isdedicated to transmission or reception. Elements 38 are arranged in twogenerally vertical columns arranged in a generally back-to-backrelationship with one another. Elements 38 comprising one of the columnsare dedicated to transmission and elements 38 comprising the other ofthe columns are dedicated to reception. The number of elements 38 ineach column is in a range of about 200 to about 600 elements and spans avertical distance of about 2 to 2.5 meters along axis R; however, inother embodiments, a different vertical span and/or number of elementscan be utilized. Transceiver 42 can control switching tree 43 toirradiate body B with only one element 38 of the transmitting column ata time and simultaneously receive with one or more elements 38 of thereceiving column. Transceiver 42 includes logic to direct successiveactivation of each element 38 of the transmitting column and thecorresponding one or more elements 38 of the receiving column to providea scan of a portion of person 22 along a vertical direction with array36. The corresponding “down range” or “time-of-flight” information canbe used to provide positional data about a corresponding portion ofperson 22 under interrogation. Further information about sucharrangements is provided in commonly owned U.S. Pat. No. 5,859,609,which is hereby incorporated by reference.

In a preferred embodiment, transceiver 42 and elements 38 of array 36are of a form suitable to transmit and/or receive electromagneticradiation selected from the range of about one Gigahertz to about oneTerahertz (about 1 GHz to about 1 THz), which corresponds to a freespace electromagnetic radiation wavelength range of about 0.3 meter (m)to about 300 micrometers (μm). In another preferred embodiment, animpulse transceiver arrangement is utilized that generates frequenciesin a range of about 200 MHz to about 15 GHz depending on the impulsewidth, which corresponds to a free space electromagnetic radiationwavelength range of about 1.5 m to about 0.02 m. In a more preferredembodiment, the frequency range is about 1 GHz to about 300 GHz with acorresponding free space wavelength range of about 0.3 meter to about 1millimeter (mm). In a most preferred embodiment, the frequency range isabout 5 GHz to about 110 GHz with a corresponding free space wavelengthrange of about 0.06 m to about 2.7 mm.

The transmission pathway for a given element 38 of the transmittingcolumn can be selected to be about the same length as the transmissionpathway for the corresponding element(s) 38 of the receiving column tosimplify calibration. Nonetheless, in other embodiments, thetransmission/reception arrangement can differ. For example, in onealternative embodiment, one or more elements 38 are used for bothtransmission and reception. In another alternative embodiment, a mixtureof both approaches is utilized. Typically, the signals received fromarray 36 are downshifted in frequency and converted into a processibleformat through the application of standard techniques. In one form,transceiver 42 is of a bi-static heterodyne Frequency ModulatedContinuous Wave (FM/CW) type like that described in U.S. Pat. No.5,859,609 (incorporated by reference herein). Commonly owned U.S. Pat.Nos. 5,557,283 and 5,455,590, each of which are incorporated byreference herein, provide several nonlimiting examples of othertransceiver arrangements. In still other embodiments, a mixture ofdifferent transceiver/sensing element configurations with overlapping ornonoverlapping frequency ranges can be utilized that may include one ormore of the impulse type, monostatic homodyne type, bi-static heterodynetype, and/or such other type as would occur to those skilled in the art.

Transceiver 42 provides the data corresponding to the array signals toone or more processors 44 of subsystem 40. Processor(s) 44 can each becomprised of one or more components of any type suitable to process thedata received from transceiver 42, including digital circuitry, analogcircuitry, or a combination of both. Processor(s) 44 can be of aprogrammable type; a dedicated, hardwired state machine; or acombination of these. For a multiple processor form; distributed,pipelined, and/or parallel processing can be utilized as appropriate. Inone arrangement, an integrated circuit form of a programmable digitalsignal processor is utilized that is capable of at least 1 Gigaflopoperation.

Memory 46 is included with processor(s) 44. Memory 46 can be of asolid-state variety, electromagnetic variety, optical variety, or acombination of these forms. Furthermore, memory 46 and can be volatile,nonvolatile, or a mixture of these types. Memory 46 can be at leastpartially integrated with processor(s) 44. Removable processor-readableMemory Device (R.M.D.) 48 is also included with processor(s) 44. R.M.D.48 can be a floppy disc, cartridge, or tape form of removableelectromagnetic recording media; an optical disc, such as a CD or DVDtype; an electrically reprogrammable solid-state type of nonvolatilememory, and/or such different variety as would occur to those skilled inthe art. In still other embodiments, R.M.D. 48 is absent.

Subsystem 40 is coupled to motor 34 to selectively control the rotationof platform 32 with processor(s) 44 and/or transceiver 42. Subsystem 40is housed in a monitoring/control station 50 that also includes one ormore operator input devices 52 and one or more display devices 54.Operator input device(s) 50 can include a keyboard, mouse or otherpointing device, a voice recognition input subsystem, and/or a differentarrangement as would occur to those skilled in the art. Operator displaydevice(s) 52 can be of a Cathode Ray Tube (CRT) type, Liquid CrystalDisplay (LCD) type, plasma type, Organic Light Emitting Diode (OLED)type, or such different type as would occur to those skilled in the art.Station 50 is arranged to be controlled by one ore more security pointoperators responsible for the operation of system 20 as furtherdescribed hereinafter.

System 20 further includes communication subsystem 60 coupled tosubsystem 40 by communication link 62. Subsystem 60 includes networkserver 63 coupled to computer network 70. Computer network 70 can beprovided in the form of a Local Area Network (LAN), a Municipal AreaNetwork (MAN), and/or a Wide Area Network (WAN) of either a private typeor publicly accessible type, such as the internet. Link 62 can beprovided by such a network or be of a dedicated communication channelvariety. Server 63 can be remotely located relative to subsystem 40.Indeed, in one embodiment, server 63 is coupled to a number of remotelylocated subsystems 40 with corresponding portals 30. In still otherembodiments, more than one server 63 can be coupled to a common portal30 and subsystem 40 arrangement. Alternatively or additionally, server63 can be an integral part of subsystem 40. For yet other embodiments,server 63, network 70, and sites 80 are absent. Indeed, removable memorydevice 48 can be used to alternatively or additionally transfer databetween subsystem 40 and other computing/processing devices.

Server 63 is operable to communicate over network 70. Computer network70 communicatively couples a number of sites 80 together. Each site 80includes computer 82 arranged to communicatively interface with computernetwork 70. Each computer 82 includes one or more operator inputdevice(s) 50 and one or more operator output device(s) 52 as previouslydescribed for subsystem 40, that are not shown to preserve clarity.Device(s) 50 and 52 at each site 80 selectively provide an operatorinput and output (I/O) capability. Computer 82 can be in the form ofanother subsystem 40, a personal computer or computer workstation,another computer server, Personal Digital Assistant (PDA), and/or adifferent configuration as would occur to those skilled in the art.While only two sites 80 are illustrated to preserve clarity, it shouldbe understood that more or fewer can be coupled via computer network 70.

Collectively, server 63, computer network 70, and sites 80 provide anarrangement to remotely communicate with station 50. The interconnectionof these components can be hardwired, wireless, or a combination ofboth. In lieu of or in addition to network 70, one or more of sites 80and server 63 could be coupled by dedicated cabling or the like.Communication over network 70 can be used to monitor performance ofstation 50, update software associated with subsystem 40, remotelyoperate station 50 or portal 30, and/or share data pertinent to therecognition of suspicious objects with system 20 as will be more fullydescribed hereinafter. In one such arrangement, one or more of sites 80are configured as a repository for data pertinent to security screeningwith system 20.

Referring additionally to the flowchart FIG. 3, one mode of operatingsystem 20 is illustrated as procedure 120. Procedure 120 is performedwith system 20 to provide image information representative of person 22carrying object 25. Procedure 120 begins with operation 121. Inoperation 121, person 22 enters portal 30 at a security checkpoint to bescreened for weapons, contraband, and/or other items/materials.Procedure 120 proceeds to initialization operation 122 that setsinterrogation index “I” to one (I=1). From operation 122, procedure 120enters interrogation loop 124 beginning with interrogation subroutine130. Interrogation subroutine 130 interrogates a portion of person 22within a field of view of array 36 as person 22 rotates on platform 32.Index I is an integer index to the number of different interrogationsubroutines 130 performed as part of procedure 120.

Referring to FIG. 4, interrogation subroutine 130 is furtherillustrated. Subroutine 130 begins with initialization operation 132 inwhich transmission index N is set to one (N=1). From operation 132,element sequencing loop 134 is entered, beginning withtransmission/reception operation 136. Index N is an integer index to thenumber of transmission/reception operations 136 performed duringsubroutine 130. In operation 136, a portion of person 22 in the field ofview of a transmitting element number “N” of array 36 is irradiated withelectromagnetic radiation and one or more corresponding receptionelements collect the reflected electromagnetic radiation in response tothe transmission. The transmitting and reception elements are selectedby logic of transceiver 42 with switching tree 43 as previouslydescribed. From operation 136, subroutine 130 proceeds to conditional138, which tests whether transmitting element number “N” is the lastelement needed to transmit (N=LAST?); where LAST is the total number ofthe transmitting elements to be activated by transceiver 42.

In one form, for each execution of subroutine 130, transmitting element“N” sweeps through a selected frequency range twice, and thecorresponding backscatter information for each of the two sweeps isreceived with a different reception element. The transmitting elementscan be staggered relative to the reception elements such thattransmitting element N aligns with a point between the two receptionelements along a common axis of the array. U.S. Pat. No. 5,557,283(incorporated by reference) describes an example of this arrangement oftransmitting and reception elements. In other forms, a differenttechnique can be utilized involving more or fewer sweeps, differenttypes of sweeps, and/or different transmitting/reception orientationsand numbers.

If the test of conditional 138 is negative (N<LAST), then incrementoperation 142 is performed, incrementing N by one (N=N+1). Loop 134returns from operation 142 to transmission/reception operation 136 forexecution with the transmitting/receiving subset of elements 38corresponding to the new, incremented value of N from operation 142. Inthis manner, elements 38 are activated in a vertical path along array 36with transceiver 42 to provide data along a contiguous region of person22.

The resolution of interrogation information obtained with transceiver 42can be enhanced by linearly sweeping through a selected ultrawidefrequency range during each operation 136. In one preferred form,transceiver 42 sweeps through a range of at least 10 GHz for eachexecution of operation 136. This sweep can occur, for example, over arange of about 10 GHz to about 20 GHz. In a more preferred form,transceiver 42 and elements 38 are arranged for a sweep range of 16 GHz.This sweep can occur, for example, over a range of about 24 GHz to about40 GHz. In one most preferred form, the ultrawide sweep range isselected such that the range resolution is generally the same as thelateral resolution. For these forms, elements 38 are selected to be of atype with a frequency response suitable for the selected sweep range,including, but not limited to the taper slot or end-fire antenna type.In another form, the transmitter can sweep through a given frequencyrange (such as 10 GHz to 20 GHz) in a pseudo-random order—sometimesknown as frequency hopping.

Loop 134 is repeated LAST number of times, sequencing through thedesired transmitting/receiving elements 38 of array 36 under the controlof transceiver 42. When the test of conditional 138 is true, theaffirmative branch proceeds to data operation 144. Data resulting fromthe execution of operation 136 is provided by transceiver 42 toprocessor(s) 44. In data operation 144, an interrogation data set isestablished for the information gathered through the repeated executionof operation 136 from N=1 through N=LAST. This data set corresponds tothe current value of integer index I and the portion illuminated duringthese executions. Initially, the interrogation data set can beaccumulated and organized by transceiver 42, processor(s) 44 or both;and then stored in memory 46 for further processing by processor(s) 44as described in connection with the remainder of procedure 120. Fromoperation 144, subroutine 130 returns to the next stage of procedure120.

Referring back to FIG. 3, procedure 120 continues with conditional 152that tests whether the final value of index I has been reached(I=TOTAL?); where TOTAL is the total number of desired executions ofloop 124 (and subroutine 130) for procedure 120. If the test ofconditional 152 is negative (I<TOTAL), procedure 120 continues toincrement operation 154 to increment index I by one (I=I+1). Loop 124then returns to subroutine 130 for the next execution until I isincremented to be equal to TOTAL.

With the execution of loop 124 TOTAL number of times, TOTAL number ofinterrogation data sets are stored in memory 46. When the test ofconditional 152 is true, procedure 120 continues with cylindricalsegmentation operation 160. In operation 160, the interrogation datasets are processed with processor(s) 44 to generate a number ofcylindrical image data sets that each correspond to an arc segment ofcylinder C. Referring to FIG. 2, arc segment S1 subtends a viewing angleV of about 90 degrees with respect to person 22. Arc segment S1 definesa cylindrical aperture CA that extends along axis R. The image data setcorresponding to arc segment S1 represents the three-dimensional surfaceof body B that is reflective with respect to the selectedelectromagnetic radiation, as if viewed through cylindrical aperture CA.In one convenient form, the image data set is defined in terms ofcylindrical coordinates, although any three-dimensional coordinatesystem can be used. Each image data set is determined from theinterrogation data gathered for the corresponding arc segment byprocessor(s) 44. Reference is made to commonly owned U.S. Pat. No.5,859,609 (incorporated herein by reference) for further descriptionabout the determination of cylindrical image data.

During operation 160, cylindrical image data sets are determined for anumber of arc segments about axis R that collectively circumscribeperson 22. In FIG. 6, eight overlapping arc segments S1, S2, S3, S4, S5,S6, S7, and S8 (collectively segments S) are illustrated with respectthe generally circular pathway P and corresponding cylinder C. SegmentsS1, S3, S5, and S7 are schematically represented by double-headed arrowsslightly to the outside of path P and segments S2, S4, S6 and S8 areschematically represented by double-headed arrows slightly inside path Pto preserve clarity. In FIG. 6, segments S each correspond to a viewingangle of about 90 degrees, and each one overlaps two others by about 45degrees. It should be understood that each different segment Scorresponds to a representation of a different portion of person 22. Inother embodiments, the viewing angle can differ and/or may be nonuniformfrom one arc segment S to the next. Alternatively or additionally,overlap may be intermittent or absent.

Procedure 120 proceeds from operation 160 to operation 162. In operation162, image data obtained for each segment S is utilized by processor(s)44 to render corresponding two-dimensional images. These images areprovided as two-dimensional arrays of pixel intensities. While thetwo-dimensional rendering can be displayed using device(s) 54 it isgenerally not desirable to do so at this stage because of thepossibility that private body parts beneath clothing may be revealed.Operation 162 results in a number of adjacent images or frames of person22 corresponding to the different arc segments S.

From operation 162, procedure 120 continues with the performance ofobject detection subroutine 170. In subroutine 170, numerical processingof image data is performed to determine if one or more suspiciousobjects are being carried by person 22, such as concealed object 25shown in FIG. 1. Referring to FIG. 5, subroutine 170 is shown in greaterdetail. Subroutine 170 begins by setting image counter F to 1 (F=1) inoperation 172. Counter F indexes the adjacent images from operation 162for processing in subroutine 170. From operation 172, subroutine 170proceeds to operation 174. In operation 174, the current image F issegmented or broken-up into a number of portions.

Referring additionally to FIG. 7, a rectangular image region IR isillustrated in three adjacent fields. In the leftmost field, imageregion IR is segmented into a first set, Set 1, of image portionsnumbered 0-17. In the middle field, image region IR is segmented into asecond set, Set 2, of image portions numbered 18-27. Image portions 0-17overlap image portions 18-27 as illustrated in the combined set in therightmost representation of image region IR in FIG. 7. In oneembodiment, the size of a segment is selected to be large enough tocontain most of the region necessary to indicate a common object type ofinterest, but not so large as to make it difficult to localize such anobject. In one arrangement utilizing Ku-band electromagnetic radiation,a segment size of about 32 by 32 pixels was found to be desirable.Nonetheless, in other embodiments, other sizes, shapes, patterns,degrees of uniformity, and/or different attributes may be varied aswould occur to those skilled in the art with or without overlappingportions.

Referring back to FIG. 5, subroutine 170 continues with operation 176.In operation 176 image data for each segment undergoes a Fouriertransformation into Fourier spatial frequency space. Operation 176 canbe performed with subsystem 40 to provide a corresponding spatialfrequency representation for each image segment. Typically, such arepresentation is complex-valued. It has been found that man-madeobjects often have a spatial frequency representation that typically hasa higher percentage of upper spatial frequencies relative to naturalobjects, such as the human body. Also, spatial frequency representationsfor man-made objects tend to dominate in certain directions in a spatialfrequency distribution over Fourier space. Such distinctions can beutilized to classify image portions suspected of revealing a man-madeobject.

Because spatial frequency information of the type provided by a Fouriertransform operation typically involves complex values, it is oftendesirable to simplify the data as part of the object detectionprocedure. In operation 178, an extraction filter is applied to extractfeatures from the spatial frequency representation that may beindicative of a man-made object. Referring additionally to FIG. 8, threedifferent feature extractor filters FR1, FR2, and FR3 are illustrated indiagrammatic form relative to Fourier space. Feature extractor FR1 is ofa ring-wedge configuration, including a half-plane of wedges and ahalf-plane of rings centered on the zeroth (0^(th)) frequency componentin Fourier space. For this extractor, the wedges provide scaleinvariance and the rings provide rotational invariance. Extractionfilter FR2 is of a sector configuration. By integrating spatialfrequencies within each sector, a set of features representing angularand radial aspects of the corresponding image segment can be generated.While not invariant, extraction filter FR2 can be utilized to identifyobjects having preferred orientations and/or sizes. Extraction filterFR3 is of a ring configuration that is rotation invariant and sorepresents a segment based on a radial spatial frequency component. Inoperation 178, one or more of these extraction filter types (FR1, FR2,FR3) can be applied and/or a different type of extraction filter may beutilized. In still other embodiments, extraction at this stage may beabsent.

In operation 180, features extracted during operation 178 are input intoa neural network defined with subsystem 40. In one form, the extractedfeatures are input into a multilayer perceptron form of neural network.The network is configured for object identification through a repetitivetraining process, such as a back propagation of error algorithm. Instill other embodiments, a different type of neural network and/ortraining technique may be additionally or alternatively utilized. In yetfurther embodiments, a different type of adaptive processing techniquecan be utilized in addition to or as an alternative to a neural network,such as fuzzy logic, an operated-assisted expert learning system, or thelike. Alternatively or additionally, nonadative processing can beutilized.

From operation 180, subroutine 170 continues with conditional 182 whichtests whether all the images have been processed in accordance withoperations 174-180. If not, counter F is indexed (F=F+1) in operation184 and loop 186 returns to operation 174 to process the next image. Ifconditional 182 is affirmative, subroutine 170 continues with operation188 in which the results obtained from loop 186 for different imageframes are compared to determine if they are consistent with one other.In one nonlimiting example with respect to arc segments S, the imageresults for arc segments S1 and S2 could be compared to each other tothe extent they overlap (see FIG. 6). Likewise overlapping image resultsfor arc segment pairs S2 and S3, S3 and S4, S4 and S5, S5 and S6, S6 andS7, S7 and S8, and S8 and S1 can be compared for consistency duringoperation 188. In other embodiments, more or fewer frames and/or adifferent frame-to-frame comparison can be made. In yet otherembodiments, there is no frame-to-frame comparison made at all.

From operation 188, conditional 190 is encountered in which framecomparison results and/or one or more other desired detectionthreshold/criterion are tested to determine if any objects of interestare indicated. If such objects are indicated, then the relative locationto the person and object image data is stored in operation 192. If thetest of conditional 190 is negative then subroutine 170 returns,bypassing operation 192. It should be understood that the performance ofany of operations 174-180 and 188, and/or conditional 190 can involvecomparing processing results to one or more threshold valves or othercriteria to determine if a corresponding image, image portion orrepresentation, image feature, or the like indicates an object ofinterest. Any such criteria can be static or dynamic in nature. Dynamiccriteria may be operator adjustable, adaptively machine adjusted, and/orselectively changed through a different technique as would occur tothose skilled in the art.

Referring back to FIG. 3, once subroutine 170 is completed, procedure120 continues with conditional 195 which tests whether any objects weredetected with subroutine 170. If objects were detected, procedure 120continues with operation 200. In operation 200, an image of each of theone or more detected objects is displayed with output device(s) 54. Theobject image or images overlay a silhouette of person 22 to showrelative location with a gender-neutral representation. In this way, thedisplayed image can be adjusted to hide/conceal body features to which aprivacy objection might be made if displayed. Alternatively, therendering can include a schematic body image similar to a mannequin, awire-frame body, or other gender-neutral representation. In one form,the suspect image features can be highlighted by a contrasting visualcharacteristic such as color, blinking/flashing or other intensityvariation, and the like. Based on such a display, an operator candetermine if further inspection is warranted, if person 22 should bedetained as a security risk, and the like. Optionally, visual and/oraudible alert signals can be generated in operation 200 to focus theoperator's attention on the person undergoing inspection and/or thecorresponding image and/or information pertaining to the classificationand detection of the objects can be displayed in text or graphic formfor operator consideration. As another option, different views of theperson and/or suspect image regions can be displayed simultaneously.Alternatively or additionally, an operator can switch between differentviews and/or can zoom-in or zoom-out to change relative size of an imagebeing displayed using input device(s) 52. In still other embodiments,false alarms can be used to refine detection criteria as/if desired.

After execution of operation 200, procedure 120 terminates. Also, ifconditional 195 is negative, procedure 120 terminates, bypassingoperation 200. Accordingly, an operator only reviews images that areindicated to show one or more objects of interest, such as a weapon orcontraband. Accordingly, privacy concerns are at the very leastreasonably reduced if not completely eliminated. In still otherembodiments, display of images of the body beneath clothing may beconditionally or unconditionally acceptable, or may be altogetherabsent. Alternatively or additionally, the information gathered withsubsystem 40 is sent via computer network 64 to one or more remote sites80. Sites 80 can perform some or all of the data processing of procedure120 in lieu of processor(s) 44. In one process, a clothed individual isnonintrusively scanned by portal 30 and the image information is sentvia server 63 and network 70 to a designated computer 82. Alternativelyor additionally, background information about a person carrying anobject of interest can be accessed via server 63 and network 70.

For procedure 120, transceiver 42 and processor(s) 44 include logic toperform the various operations described. This logic can be in the formof software programming instructions, firmware, and/or of a hardwiredform, just to name a few. Furthermore such logic can be in the form ofone or more signals carried with memory 46, R.M.D. 48, and/or one ormore parts of computer network 70. In one example, logic signals toperform one or more operations is transmitted to or from processor(s) 44via network 70. Alternatively or additionally, programming forprocessor(s) 44 is transported or disseminated through R.M.D. 48 and/orone or more other storage devices.

FIGS. 9 and 10 illustrate system 320 of another embodiment of thepresent invention that can be used to perform procedure 120. System 320illuminates person 322 which selected electromagnetic radiation in themanner described in connection with system 20. For system 320, person322 is wearing clothing articles that conceal object 325 shown inphantom. As in the previously described embodiment, system 320 can beused to interrogate inanimate objects as well. System 320 includes dualplanar panel scanning portal 330 and processing subsystem 340 includedin monitoring/control station 350. Portal 330 is coupled to processingsubsystem 340 and can be configured the same as subsystem 40, accountingfor differences in the scanning technique of portal 330 as is more fullydescribed hereinafter. Station 350 includes one or more operator inputand output devices as described in connection with system 20 that arecoupled to subsystem 340. Station 350 can be arranged to provide asecurity checkpoint operator interface adjacent portal 330.

Portal 330 includes stationary platform 332 arranged to support person322 and overhead motor/drive subsystem 334. Under the control ofsubsystem 340, subsystem 334 is configured to controllably slide each oftwo arrays 336 along corresponding guide rods 337 up and down withrespect to vertical axis VA. Correspondingly, arrays 336 each follow agenerally linear path on opposite sides of person 322 and are eachincluded within a corresponding opposing panel 338. FIG. 10 shows one ofpanels 338 in greater detail utilizing a partial cut-away view. Insystem 320, subsystem 340 is configured the same as subsystem 40 ofsystem 20, is likewise arranged to perform procedure 120, and caninclude a transceiver and/or switching tree as appropriate. However,during performance of procedure 120, the operation of subsystem 340accounts for the movement of array 336 relative to person 322 in alinear, translational manner instead of a rotational manner as describedin connection with system 20. Also, because the opposing arrays 336 donot provide overlapping frames as in the case of system 20, operation188 of subroutine 170 is not performed and appropriate adjustments areotherwise made to procedure 120. System 320 can include one or moreencoders (not shown) operably coupled to system 340 and/or otherdevices/techniques to track position of arrays 336 relative to platform332. System 320 can further include a communication subsystem (notshown) the same as subsystem 60 to remotely communicate with subsystem340.

In one particular arrangement, panels 338 are spaced apart by about 1.22meters and a frequency sweep in the Ku-band from about 12.5-18 GHz isperformed to provide a lateral resolution of about 1 centimeter and adepth resolution of about 2.7 centimeters. For this arrangement, arrays336 each include two subarrays of about 56 elements each that arearranged back-to-back. One subarray is dedicated to transmission and theother subarray is dedicated to reception within each array 336. In oneform, each subarray is fabricated with slot-line antennas spaced apartfrom one another by about 2 centimeters. During operation, each subarrayis electronically scanned from element to element as the scanner movesrapidly over the vertical length of person 322. As the array moves, anumber of scans are performed with array 336. During each scan, only oneelement of the transmitting subarray is illuminating the person and onlyone element of the receiving subarray is collecting reflectedelectromagnetic radiation at any given time. Accordingly, eachtransmitting element and each receiving element is activated inaccordance with a desired sequence during the scan. In a FM/CWheterodyne transceiver configuration of this arrangement, the 5.5. GHzfrequency sweep is performed in about 12.75 microseconds. In still otherembodiments, a different number, size, or type of linear arrayarrangement can be utilized as would occur to those skilled in the art.In still other examples, different types of rotating and/or linearscanning arrays can be utilized separately or in combination.

FIG. 11 illustrates interrogation system 420 of another embodiment ofthe present invention. System 420 illuminates person 422 with selectedelectromagnetic radiation in the manner described in connection withsystem 20. For system 420, person 422 is wearing clothing articles 424 aand 424 b that hide object 425. As in previously described embodiments,system 420 can be used to interrogate inanimate objects as well.

System 420 includes scanning booth 430 coupled to control and processingsubsystem 440. Scanning booth 430 includes stationary platform 432arranged to support person 422 and frame 433 to support motor 434coupled to array 436. In contrast to the platform rotation of portal 30and translational movement associated with portal 330, scanning booth430 selectively rotates array 436 about rotational axis R and platform432 during interrogation. For this arrangement, array 436 follows agenerally circular pathway to provide a corresponding imaginary cylinderabout platform 432. In one form suitable for scanning a person in thestanding position, the radius of this cylinder is about 1 meter. Array436 is otherwise configured the same as array 36.

In system 420, subsystem 440 is configured the same as subsystem 40 ofsystem 20 and is likewise arranged to perform procedure 120 to detectconcealed/hidden objects. However, during the performance of procedure120, the operation of subsystem 440 accounts for the movement of array436 relative to platform 432 instead of the movement of platform 32relative to array 36 as for system 20. System 420 can include one ormore encoders (not shown) operatively coupled to subsystem 440 and/orother devices/techniques to track the position of array 436 relative toplatform 432. System 420 can further include a communication subsystem(not shown) the same as subsystem 60 to remotely communicate withsubsystem 440.

FIG. 12 illustrates electromagnetic radiation interrogation system 520of yet another embodiment of the present invention. System 520illuminates person 522 with selected electromagnetic radiation of thetype previously described. For system 520, person 522 is wearinggarments/clothing designated by reference numerals 524 a and 524 b thatconceal object 525. As in previously described embodiments, system 520can be used to interrogate animate or inanimate objects.

System 520 includes scanning booth 530 coupled to control and processingsubsystem 540. Scanning booth 530 includes frame 533 arranged to receiveperson 522 and support array 536. In contrast to the linearly orientedarrays 36, 336, and 436 of previously described systems 20 and 420,array 536 is arranged as a ring or hoop generally centered with respectto centerline vertical axis CVA. A number of electromagnetic radiationtransmitting/receiving elements are arranged in a generally circularpathway along the ring. These elements operate to interrogate person 522with electromagnetic radiation including one or more wavelengths in themillimeter, microwave, and/or adjacent wavelength bands. Array 536 isarranged for translational movement along axis CVA to scan person 522 asrepresented by arrow T. One or more motors or other prime mover(s) (notshown) are utilized to selectively move array 536 along axis CVA.

Referring further to the partial top view of FIG. 13, array 536 is sizedwith opening 537 to receive person 522 therethrough as array 536 movesup and down along axis CVA. In FIG. 13, axis CVA is generallyperpendicular to the view plane and is represented by crosshairs. Withthe vertical motion of array 536, an imaginary cylinder is defined aboutperson 522 in accordance with the circular path defined by the arrayring; however, neither person 522 nor array 536 is rotated relative tothe other, instead translational movement of array 536 is used to scanperson 522 vertically.

Subsystem 540 is configured the same as subsystems 40, 340 and 440 andis operable to perform procedure 120, except that processing ofsubsystem 540 is adapted to account for the vertical translationalmovement of array 436 with its circumferential arrangement. System 520can further include a communication subsystem (not shown) the same assubsystem 60 to remotely communicate with subsystem 440. Like previouslydescribed embodiments, system 520 is used to detect concealed objects asexplained in connect with procedure 120.

Compared to array 36, a larger number of transmitting/receiving elementsis typically needed for array 536 to have a comparable resolution topreviously described embodiments. In one comparison, between 500 and2000 transmitting/receiving elements would be desired for array 536versus 200 to 600 for array 36 for comparable resolution, depending onthe frequency band selected. However, under appropriate conditions,scanning booth 530 can perform a scan substantially faster than portal30. In one nonlimiting example, the scan time for portal 30 is in arange of about 10 to 20 seconds versus about 2 to 5 seconds for scanningbooth 530.

In a further embodiment of the present invention, the body undergoinginterrogation and the array both move. In one such example, arrayelements are arranged in an arc segment that can move vertically whilethe body rotates. In another example, both the array and body rotate.The processing of interrogation data can be adjusted for these differentmotion patterns using techniques known to those skilled in the art.

In another embodiment, the interrogation and corresponding imageinformation do not correspond to the full circumference of the bodyundergoing interrogation. Instead, the segment of interest can be lessthan 360 degrees. For such embodiments, the image information can stillbe determined by combining data corresponding to two or more differentview angles. Alternatively or additionally, less than the full height,width, and/or length of the subject may be scanned in other embodiments.For such alternatives, the array size and/or scanning pattern can becorrespondingly adjusted.

In one further embodiment, the image information is obtained inaccordance with procedure 120 and/or system 20, 320, 420, or 520 isadditionally utilized to identify an individual. One form of thisembodiment includes a technique to control access to a restricted area,comprising: scanning an individual attempting to gain access to therestricted area; determining whether the individual is concealing anyobjects from the scan; comparing one or more aspects of thecorresponding image information regarding features of the individual todata stored for those permitted access to the restricted area; andallowing access to the restricted area by the individual if there is afavorable comparison and no suspicious concealed objects are indicated.The determination of a match can be used to activate a gate or otheraccess control device. In another embodiment, image information gatheredwith system 20, 320, 420, and/or 520 is additionally or alternativelyused to identify individuals for which access should not be permitted,such as suspected criminals, known terrorists, and the like. In one morevariation of such embodiments, one or more other biometrics (such as afingerprint, palm print, retina image, vocal pattern, etc.) of theindividual are compared in addition to the topographical representationrelated data as part of the determination of whether to allow access.The features used for identification can be changed for each access toreduce the likelihood that the access control measures will becircumvented. Alternatively or additionally, object detection inaccordance with the present invention can be used to determine if anindividual is taking an object from an area without permission to do so.Any of these embodiments can be provided as a method, apparatus, system,and/or device.

All publications and patent applications cited in this specification areherein incorporated by reference as if each individual publication orpatent application were specifically and individually indicated to beincorporated by reference. Further, any theory, mechanism of operation,proof, or finding stated herein is meant to further enhanceunderstanding of the present invention, and is not intended to limit thepresent invention in any way to such theory, mechanism of operation,proof, or finding. While the invention has been illustrated anddescribed in detail in the drawings and foregoing description, the sameis to be considered as illustrative and not restrictive in character, itbeing understood that only selected embodiments have been shown anddescribed and that all equivalents, changes, and modifications that comewithin the spirit of the inventions as defined herein or by thefollowing claims are desired to be protected.

1. A method, comprising: irradiating a person at least partially covered with clothing; detecting electromagnetic radiation within a frequency range of about 200 MHz to about 1 THz reflected from a surface beneath the clothing in response to said irradiating; establishing data representative of an image of the person from the electromagnetic radiation; determining a number of data sets from the data, the data sets each corresponding to a spatial frequency representation of a different portion of the image; and adaptively processing each of the data sets to identify a man-made object being carried by the person beneath the clothing.
 2. The method of claim 1, wherein said determining includes performing a Fourier transform operation for each of a number of different portions of the data to provide a corresponding number of complex spatial frequency data representations.
 3. The method of claim 2, wherein said determining further includes applying an image feature extraction filter to each of the complex spatial frequency data representations to correspondingly provide the data sets.
 4. The method of claim 3, wherein said extracting is performed with at least one of a radially invariant and an angular invariant filter.
 5. The method of claim 1, wherein said adaptively processing is performed with a neural network.
 6. The method of claim 1, wherein the man-made object is at least one of a weapon and contraband.
 7. The method of claim 1, which includes displaying an image of at least a portion of the man-made object.
 8. A method, comprising: establishing data corresponding to an image of a concealed surface by irradiating with electromagnetic radiation including one or more frequencies in a range of about 200 MHz to about 1 THz; generating a data set corresponding to a spatial frequency representation of at least a portion of the image from the data; and identifying a concealed man-made object by analyzing the data set with a neural network.
 9. The method of claim 8, which includes displaying an image of at least a portion of the man-made object.
 10. The method of claim 8, wherein said establishing is performed by scanning a person in a portal at a security checkpoint with the electromagnetic radiation.
 11. The method of claim 8, wherein said generating includes performing a Fourier transform operation and extracting the data set from results of the Fourier transform operation.
 12. The method of claim 8, wherein the range is about 5 GHz to about 110 GHz.
 13. The method of claim 8, wherein the concealed man-made object is being carried by a person beneath clothing during said establishing and the man-made object is at least one of a weapon and contraband.
 14. The method of claim 8, which includes generating a number of overlapping image frames and wherein said identifying further includes comparing information between two or more of the frames.
 15. A method, comprising: irradiating a person at least partially covered with clothing; detecting electromagnetic radiation reflected from a surface beneath the clothing in response to said irradiating; establishing data corresponding to a spatial frequency representation of the surface from the electromagnetic radiation; and analyzing the data with a neural network to identify a man-made object being carried by the person beneath the clothing.
 16. The method of claim 15, which includes determining a data set corresponding to an image of the surface from the electromagnetic radiation.
 17. The method of claim 16, wherein said establishing includes: determining a number of image portions from the data set; performing a Fourier transform operation for each of the image portions to provide a corresponding number of spatial frequency image portion representations; and applying a feature extraction filter to each of the spatial frequency image portion representations.
 18. The method of claim 17, wherein the data corresponds to the output of the feature extraction filter for one or more of the spatial frequency image portion representations.
 19. The method of claim 15, which includes displaying an image including the man-made object.
 20. The method of claim 15, wherein the electromagnetic radiation includes one or more frequencies is a range of about 200 MHz through about 1 THz and the man-made object is at least one of a weapon and contraband.
 21. A method, comprising: irradiating a person at least partially covered by clothing with electromagnetic radiation including one or more frequencies in a range of 200 MHz to about 1 THz; in response to said irradiating, establishing data representative of an image corresponding to appearance of one or more private body parts under the clothing; determining a number of data sets each corresponding to a respective one of a number of different image portions; numerically processing the data sets relative to one or more criteria to evaluate if one or more of the different image portions reveals a man-made object beneath the clothing; and if the one or more criteria are satisfied, displaying an image of the man-made object relative to a location on the person.
 22. The method of claim 21, which includes inhibiting said displaying if the one or more criteria are not satisfied.
 23. The method of claim 21, wherein said displaying includes showing the person with a gender-neutral representation.
 24. The method of claim 21, wherein the man-made object is at least one of a weapon and contraband.
 25. The method of claim 21, wherein the data sets each correspond to a spatial frequency representation of the respective one of the different image portions.
 26. The method of claim 25, wherein said numerically processing includes: performing a Fourier transform to provide spatial frequency data for each of the different image portions; applying an image feature extraction filter to the spatial frequency data for each of the different image portions to provide a corresponding one of the data sets; and analyzing each of the data sets with a neural network, the one or more criteria including neural network weight values.
 27. A system, comprising: an array operable to interrogate a person with electromagnetic radiation at one or more frequencies in a range of about 200 MHz to about 1 THz; and one or more processors operable to establish data corresponding to an image of a surface beneath clothing of the person from one or more input signals from the array and generate a number of data sets each corresponding to a spatial frequency representation of a different portion of the image from the data, the one or more processors being further operable to analyze the data sets with a neural network to detect if the person is carrying a man-made object concealed by the clothing.
 28. The system of claim 27, further comprising a display device responsive to said one or more processors to provide at least one image corresponding to the man-made object if the man-made object is detected.
 29. The system of claim 27, further comprising a platform proximate to said array to support the person and a motor to move at least one of the array and the platform relative to another of the array and the platform to perform a security scan of the person at a security checkpoint.
 30. The system of claim 27, wherein the processor is further operable to generate image data corresponding to a number of cylindrical images of the person.
 31. The system of claim 27, further comprising: means for processing portions of the data corresponding to portions of the image; means for transforming the portions of the data to corresponding sets of spatial frequency image representation data; and means for extracting features from the sets of spatial frequency image representation data for analysis by the neural network, the data sets representing one or more features provided by said extracting means.
 32. The system of claim 27, wherein the array is operable to provide the electromagnetic radiation at a plurality of different frequencies spanning at least a 10 GHz band.
 33. An apparatus, comprising: a device carrying logic executable by one or more processors to analyze data corresponding to an image of a person obtained from electromagnetic radiation including one or more frequencies in a range of about 200 MHz to about 1 THz, the logic being further operable to generate a number of data sets each corresponding to a spatial frequency representation of a respective one of a number of different portions of the image, adaptively process each of the data sets relative to one or more criteria to determine if one or more of the different portions of the image show a man-made object concealed by clothing of the person, and provide one or more output signals to display at least a portion of the man-made object relative to a location on the person if the one or more criteria are satisfied.
 34. The apparatus of claim 33, wherein the device is in the form of a processor-readable memory and the logic is in the form of a number of instructions stored in the memory.
 35. The apparatus of claim 33, wherein the device includes one or more parts of a computer network and the logic is encoded in one or more signals for transmission over the computer network.
 36. The apparatus of claim 33, wherein the logic is further operable to perform a Fourier transform operation with different portions of the data to correspondingly provide a number of sets of spatial frequency data.
 37. The apparatus of claim 36, wherein the logic is further operable to apply an image feature filter to each of the sets of spatial frequency data to correspondingly provide the data sets.
 38. The apparatus of claim 33, further comprising a display device responsive to the one or more output signals to provide an image of the man-made object at the location on a gender-neutral representation of the person.
 39. The apparatus of claim 33, wherein the logic defines a neural network to adaptively process the data sets. 